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    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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    <table align="center" border="1" cellspacing="0" width="500" height="300">
        <caption>合并单元格</caption>
        <tr>
            <th></th>
            <!-- 跨列合并，先找到要合并的几个单元格，然后将该单元格设置为colspan或者rowspan，设置了之后将被替换的单元格删除 -->
            <th colspan="2"></th>
            
        </tr>
        <tr>

            <th rowspan="2"></th>
            <th></th>
            <th></th>
        </tr>
        <tr>
           
            <th></th>
            <th></th>
        </tr>
    </table>
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